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Performance evaluation of circulating fluidized bed incineration of municipal solid waste by multivariateoutlier detection in China

Hua Tao, Pinjing He, Yi Zhang, Wenjie Sun

《环境科学与工程前沿(英文)》 2017年 第11卷 第6期 doi: 10.1007/s11783-017-0945-3

摘要: This first nationwide survey was conducted to evaluate the overall performance of the circulating fluidized bed (CFB) incineration of municipal solid waste (MSW) in 2014-2015 in China. Total 23 CFB incineration power plants were evaluated. The data for monthly average flue gas emission of particles, CO, NO , SO and HCl were collected over 12 consecutive months. The data were analyzed to assess the overall performance of CFB incineration by applying the Mahalanobis distance as a multivariate outlier detection method. Although the flue gas emission parameters had met the Chinese national emission standards, there were 11 total outliers (abnormal behavior) detected in 6 out of 23 CFB incineration power plants from the perspective of the MSW incineration performance. The results demonstrate that it is more important for a better performance of CFBs to reduce the frequencies of the MSW load changes, rather than the magnitudes of the MSW load changes, particularly reducing the frequencies in the range of 10% and more of the load changes, under the same and stable conditions. Furthermore, the overloading occurs more often than the underloading during the operation of the CFB incineration power plants in China. The frequent overloading is 0% to 30% of the designed capacity. To achieve the stable performance of CFBs in practice, an appropriately designed MSW storage capacity is suggested to build in a plant to buffer and reduce the frequency of the load changes.

关键词: Municipal solid waste     Incineration     Circulating fluidized bed     Load change     Multivariate outlier detection    

Image-based fall detection and classification of a user with a walking support system

Sajjad TAGHVAEI, Kazuhiro KOSUGE

《机械工程前沿(英文)》 2018年 第13卷 第3期   页码 427-441 doi: 10.1007/s11465-017-0465-7

摘要:

The classification of visual human action is important in the development of systems that interact with humans. This study investigates an image-based classification of the human state while using a walking support system to improve the safety and dependability of these systems. We categorize the possible human behavior while utilizing a walker robot into eight states (i.e., sitting, standing, walking, and five falling types), and propose two different methods, namely, normal distribution and hidden Markov models (HMMs), to detect and recognize these states. The visual feature for the state classification is the centroid position of the upper body, which is extracted from the user’s depth images. The first method shows that the centroid position follows a normal distribution while walking, which can be adopted to detect any non-walking state. The second method implements HMMs to detect and recognize these states. We then measure and compare the performance of both methods. The classification results are employed to control the motion of a passive-type walker (called “RT Walker”) by activating its brakes in non-walking states. Thus, the system can be used for sit/stand support and fall prevention. The experiments are performed with four subjects, including an experienced physiotherapist. Results show that the algorithm can be adapted to the new user’s motion pattern within 40 s, with a fall detection rate of 96.25% and state classification rate of 81.0%. The proposed method can be implemented to other abnormality detection/classification applications that employ depth image-sensing devices.

关键词: fall detection     walking support     hidden Markov model     multivariate analysis    

Unknown fault detection for EGT multi-temperature signals based on self-supervised feature learning and

《能源前沿(英文)》 2023年 第17卷 第4期   页码 527-544 doi: 10.1007/s11708-023-0880-x

摘要: Intelligent power systems can improve operational efficiency by installing a large number of sensors. Data-based methods of supervised learning have gained popularity because of available Big Data and computing resources. However, the common paradigm of the loss function in supervised learning requires large amounts of labeled data and cannot process unlabeled data. The scarcity of fault data and a large amount of normal data in practical use pose great challenges to fault detection algorithms. Moreover, sensor data faults in power systems are dynamically changing and pose another challenge. Therefore, a fault detection method based on self-supervised feature learning was proposed to address the above two challenges. First, self-supervised learning was employed to extract features under various working conditions only using large amounts of normal data. The self-supervised representation learning uses a sequence-based Triplet Loss. The extracted features of large amounts of normal data are then fed into a unary classifier. The proposed method is validated on exhaust gas temperatures (EGTs) of a real-world 9F gas turbine with sudden, progressive, and hybrid faults. A comprehensive comparison study was also conducted with various feature extractors and unary classifiers. The results show that the proposed method can achieve a relatively high recall for all kinds of typical faults. The model can detect progressive faults very quickly and achieve improved results for comparison without feature extractors in terms of F1 score.

关键词: fault detection     unary classification     self-supervised representation learning     multivariate nonlinear time series    

Modeling of unconfined compressive strength of soil-RAP blend stabilized with Portland cement using multivariate

Ali Reza GHANIZADEH, Morteza RAHROVAN

《结构与土木工程前沿(英文)》 2019年 第13卷 第4期   页码 787-799 doi: 10.1007/s11709-019-0516-8

摘要: The recycled layer in full-depth reclamation (FDR) method is a mixture of coarse aggregates and reclaimed asphalt pavement (RAP) which is stabilized by a stabilizer agent. For design and quality control of the final product in FDR method, the unconfined compressive strength of stabilized material should be known. This paper aims to develop a mathematical model for predicting the unconfined compressive strength (UCS) of soil-RAP blend stabilized with Portland cement based on multivariate adaptive regression spline (MARS). To this end, two different aggregate materials were mixed with different percentages of RAP and then stabilized by different percentages of Portland cement. For training and testing of MARS model, total of 64 experimental UCS data were employed. Predictors or independent variables in the developed model are percentage of RAP, percentage of cement, optimum moisture content, percent passing of #200 sieve, and curing time. The results demonstrate that MARS has a great ability for prediction of the UCS in case of soil-RAP blend stabilized with Portland cement ( is more than 0.97). Sensitivity analysis of the proposed model showed that the cement, optimum moisture content, and percent passing of #200 sieve are the most influential parameters on the UCS of FDR layer.

关键词: full-depth reclamation     soil-reclaimed asphalt pavement blend     Portland cement     unconfined compressive strength     multivariate adaptive regression spline    

Assessment of temporal and spatial variations in water quality using multivariate statistical methods

Xue LI,Pengjing LI,Dong WANG,Yuqiu WANG

《环境科学与工程前沿(英文)》 2014年 第8卷 第6期   页码 895-904 doi: 10.1007/s11783-014-0736-z

摘要: This study evaluated the temporal and spatial variations of water quality data sets for the Xin'anjiang River through the use of multivariate statistical techniques, including cluster analysis (CA), discriminant analysis (DA), correlation analysis, and principal component analysis (PCA). The water samples, measured by ten parameters, were collected every month for three years (2008–2010) from eight sampling stations located along the river. The hierarchical CA classified the 12 months into three periods (First, Second and Third Period) and the eight sampling sites into three groups (Groups 1, 2 and 3) based on seasonal differences and various pollution levels caused by physicochemical properties and anthropogenic activities. DA identified three significant parameters (temperature, pH and ) to distinguish temporal groups with close to 76% correct assignment. The DA also discovered five parameters (temperature, electricity conductivity, total nitrogen, chemical oxygen demand and total phosphorus) for spatial variation analysis, with 80.56% correct assignment. The non–parametric correlation coefficient (Spearman R) explained the relationship between the water quality parameters and the basin characteristics, and the GIS made the results visual and direct. The PCA identified four PCs for Groups 1 and 2, and three PCs for Group 3. These PCs captured 68.94%, 67.48% and 70.35% of the total variance of Groups 1, 2 and 3, respectively. Although natural pollution affects the Xin'anjiang River, the main sources of pollution included agricultural activities, industrial waste, and domestic wastewater.

关键词: Xin'anjiang River     multivariable statistical analysis     temporal variation     spatial variation     water quality    

基于多元数据的交通视角超大特大城市中心城区合理规模研究

陆化普,柏卓彤,吴洲豪,傅志寰

《中国工程科学》 2022年 第24卷 第6期   页码 146-153 doi: 10.15302/J-SSCAE-2022.06.013

摘要:

超大特大城市中心城区高强度连片开发、人口密度大、城市功能集中,是我国城市问题表现最为突出的区域范围;着眼集中于中心城区的大城市病破解问题,开展超大特大城市中心城区的合理规模分析论证具有迫切性。本文提出了通勤出行时间是超大特大城市中心城区合理规模的核心控制因素这一基本判断;采用大数据分析及聚类分析方法,结合城市多类土地利用的兴趣点数据、街道行政边界的地理信息系统数据,识别了我国10 个超大特大城市的现状中心城区范围;基于网络地图路径规划、手机信令数据校核,分析评价了现状交通效率;以量化分析为基础,获得了特大城市中心城区合理规模的论证结果。研究表明,当前一些超大特大城市的中心城区范围不能满足以人为本的幸福通勤出行需求;结合未来交通运输领域技术发展、治理水平提高等因素,13~15 km当量半径是超大特大城市中心城区合理规模范围的上限。

关键词: 合理规模;多元数据;中心城区;超大特大城市;幸福感    

三峡库区香溪河流域多变量生态水文风险的不确定性分析 Article

Yurui Fan,Guohe Huang,Yin Zhang,Yongping Li

《工程(英文)》 2018年 第4卷 第5期   页码 617-626 doi: 10.1016/j.eng.2018.06.006

摘要:

本研究基于copula函数开发了一种多变量生态水文风险评估框架,用于分析三峡库区香溪河流域极端生态水文事件的发生频率。通过马尔可夫链蒙特卡罗(MCMC)方法量化边缘分布及copula函数中参数的不确定性,并基于后验概率揭示联合重现期的内在不确定性,同时可进一步得到双变量及多变量风险的概率特征。研究结果显示所得概率模型的预测区间可很好地匹配观测值,尤其对洪水持续时间而言。同时,“AND”联合重现期的不确定性随着单个洪水变量重现期的增加而增加。此外,低设计流量及高服务年限可能导致高洪水风险且伴随大量不确定性。

关键词: 洪水风险     copula     多变量水文频率分析     概率分布     马尔科夫链蒙特卡罗    

扩大多元回归方法在跨组学研究中的范围 Article

Xiaoxi Hu, Yue Ma, Yakun Xu, Peiyao Zhao, Jun Wang

《工程(英文)》 2021年 第7卷 第12期   页码 1725-1731 doi: 10.1016/j.eng.2020.05.028

摘要:

近年来科技的进步和发展使得高维数据急剧增加,研究人员对合适且有效的多元回归方法的需求也随之增长。许多传统的多元分析方法如主成分分析等已广泛应用于投资分析、图像识别和群体遗传结构分析等研究领域。然而,这些常见的方法存在其局限性,即忽略了响应之间的相关性和变量选择效率低的问题。因此,本文引入了降秩回归方法及其扩展形式——稀疏降秩回归和行稀疏的子空间辅助回归,这些方法有望满足上述需求,从而提高回归模型的可解释性。我们通过开展仿真研究来评估它们的效果,并将它们与其他几种变量选择方法进行比较。对于不同的应用场景,我们也提供了基于预测能力和变量选择精度的选择建议。最后,为了证明这些方法在微生物组研究领域的实用价值,我们将所选择的方法应用于实际种群水平的微生物组数据,结果验证了我们方法的有效性。该方法的扩展形式为未来的组学研究特别是多元回归研究提供了有价值的指导,并为微生物组学及其相关研究领域的新发现奠定了基础。

关键词: 多元回归方法     降秩回归     稀疏性     降维     变量选择    

Spatio-temporal variations of water quality in Yuqiao Reservoir Basin, North China

Yuan XU,Ruqin XIE,Yuqiu WANG,Jian SHA

《环境科学与工程前沿(英文)》 2015年 第9卷 第4期   页码 649-664 doi: 10.1007/s11783-014-0702-9

摘要: Fuzzy comprehensive assessment and multivariate statistical techniques including cluster analysis, discriminant analysis, principal component analysis, and factor analysis were applied to analyze the water quality status of Yuqiao Reservoir Basin, North China, for assessing its spatio-temporal variations and identifying potential pollution sources. In this paper, we considered data for 14 water quality parameters collected during 1990–2004 at 7 water quality monitoring sites. The results of fuzzy comprehensive assessment revealed that water quality in Yuqiao Reservoir Basin showed a downtrend from 1990 to 2001 with fluctuation, and a slowly upward trend after 2001. The major water quality belonged to Class III and IV. Besides, hierarchical cluster analysis divided 7 monitoring sites into two groups (Group A and B), and 12 months into three periods (low-flow (LF), normal-flow (NF), and high-flow (HF) period). Temp, pH, SS, T-har, DO, NO -N and TP were identified as significant variables affecting spatial variations, and Temp, pH and NO -N were identified as significant variables affecting temporal variations by discriminant analysis. Factor analysis identified four latent pollution sources for water quality variations: nutrient pollution, organic pollution, inorganic pollution, and natural pollution. Moreover, for Group A regions, pollution inputs mainly came from domestic wastewater and industrial sewage. For Group B regions, it is more likely that water pollution resulted from the combined effects of domestic wastewater, hospital wastewater, agriculture runoff, and fishpond discharge, as well as the incoming water from upstream.

关键词: Fuzzy comprehensive assessment     multivariate statistical analysis     water quality    

Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory, and fuzzy detection theory in regions of Mexico

Pedro PONCE, Therese PEFFER, Arturo MOLINA

《能源前沿(英文)》 2019年 第13卷 第3期   页码 522-538 doi: 10.1007/s11708-018-0562-2

摘要: It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes; thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable STs or when they do not use the STs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the STs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (SDT), fuzzy detection theory (FDT), and chi-square (CS) test in order to understand the perceptions and beliefs of end users about the use of STs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about STs are not met. It also promotes the technological and social development of STs such that they are relatively more accepted in complex electrical grids such as smart grids.

关键词: thermostats     perceptions     beliefs     signal detection theory (SDT)     fuzzy signal detection theory (FSDT)     chi-square (CS) test    

Advances in airborne microorganisms detection using biosensors: A critical review

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-021-1420-8

摘要:

Humanity has been facing the threat of a variety of infectious diseases. Airborne microorganisms can cause airborne infectious diseases, which spread rapidly and extensively, causing huge losses to human society on a global scale. In recent years, the detection technology for airborne microorganisms has developed rapidly; it can be roughly divided into biochemical, immune, and molecular technologies.

关键词: Biosensor     Airborne microorganisms     Microbiological detection technology    

Recent advances in SERS detection of perchlorate

Jumin Hao, Xiaoguang Meng

《化学科学与工程前沿(英文)》 2017年 第11卷 第3期   页码 448-464 doi: 10.1007/s11705-017-1611-9

摘要: Perchlorate has recently emerged as a widespread environmental contaminant of healthy concern. Development of novel detection methods for perchlorate with the potential for field use has been an urgent need. The investigation has shown that surface-enhanced Raman scattering (SERS) technique has great potential to become a practical analysis tool for the rapid screening and routine monitoring of perchlorate in the field, particularly when coupled with portable/handheld Raman spectrometers. In this review article, we summarize progress made in SERS analysis of perchlorate in water and other media with an emphasis on the development of SERS substrates for perchlorate detection. The potential of this technique for fast screening and field testing of perchlorate-contaminated environmental samples is discussed. The challenges and possible solutions are also addressed, aiming to provide a better understanding on the development directions in the research field.

关键词: perchlorate     SERS     detection     substrate     modification     nanostructure    

基于先验形状和局部统计的血管影像图像分割方法 Research Articles

Yun TIAN, Zi-feng LIU, Shi-feng ZHAO

《信息与电子工程前沿(英文)》 2019年 第20卷 第8期   页码 1099-1108 doi: 10.1631/FITEE.1800129

摘要: 快速准确地从医学图像中提取血管结构是许多临床医疗的基础。然而,大多数血管分割方法忽略了分割结果中孤立点和冗余点的存在。本文提出一种基于先验形状和局部统计的血管分割方法,能有效消除异常值并精确分割粗细血管。首先,定义了一种改进的血管滤波器,用于量化每个体素属于管状结构的可能性;其次,执行匹配和连接操作以获得血管掩模;最后,在血管掩模基础上实现基于局部统计的区域生长方法,得到较为完整的无外围值的血管树。与Frangi方法以及Yang方法在实际血管造影图像上的实验和比较,证明该方法在保持血管分支连通的同时,可以有效去除异常值。

关键词: 血管滤波器;邻域;血管分割;外围值    

A fast antibiotic detection method for simplified pretreatment through spectra-based machine learning

《环境科学与工程前沿(英文)》 2022年 第16卷 第3期 doi: 10.1007/s11783-021-1472-9

摘要:

• A spectral machine learning approach is proposed for predicting mixed antibiotic.

关键词: Antibiotic contamination     Spectral detection     Machine learning    

Field investigation of intelligent compaction for hot mix asphalt resurfacing

Wei HU,Xiang SHU,Baoshan HUANG,Mark WOODS

《结构与土木工程前沿(英文)》 2017年 第11卷 第1期   页码 47-55 doi: 10.1007/s11709-016-0362-x

摘要:

Intelligent compaction (IC) is a relatively new technology for asphalt paving industry. The present study evaluated the effectiveness and potential issues of the IC technology for flexible pavement resurfacing construction using two field projects. In the first project, a geostatistical semivariogram model was established and the parameters derived from it were compared with univariate statistical parameters for the Compaction Meter Value (CMV) data. Further analyses illustrated the effect of temperature on the CMV value and compaction uniformity. In the second project, a multivariate analysis was performed between in situ tests and IC data. The possibility of combining various IC data to predict the asphalt layer density and improve the current quality control and assurance system was discussed.

关键词: intelligent compaction     compaction meter value (CMV)     semivariogram     multivariate analysis    

标题 作者 时间 类型 操作

Performance evaluation of circulating fluidized bed incineration of municipal solid waste by multivariateoutlier detection in China

Hua Tao, Pinjing He, Yi Zhang, Wenjie Sun

期刊论文

Image-based fall detection and classification of a user with a walking support system

Sajjad TAGHVAEI, Kazuhiro KOSUGE

期刊论文

Unknown fault detection for EGT multi-temperature signals based on self-supervised feature learning and

期刊论文

Modeling of unconfined compressive strength of soil-RAP blend stabilized with Portland cement using multivariate

Ali Reza GHANIZADEH, Morteza RAHROVAN

期刊论文

Assessment of temporal and spatial variations in water quality using multivariate statistical methods

Xue LI,Pengjing LI,Dong WANG,Yuqiu WANG

期刊论文

基于多元数据的交通视角超大特大城市中心城区合理规模研究

陆化普,柏卓彤,吴洲豪,傅志寰

期刊论文

三峡库区香溪河流域多变量生态水文风险的不确定性分析

Yurui Fan,Guohe Huang,Yin Zhang,Yongping Li

期刊论文

扩大多元回归方法在跨组学研究中的范围

Xiaoxi Hu, Yue Ma, Yakun Xu, Peiyao Zhao, Jun Wang

期刊论文

Spatio-temporal variations of water quality in Yuqiao Reservoir Basin, North China

Yuan XU,Ruqin XIE,Yuqiu WANG,Jian SHA

期刊论文

Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory, and fuzzy detection theory in regions of Mexico

Pedro PONCE, Therese PEFFER, Arturo MOLINA

期刊论文

Advances in airborne microorganisms detection using biosensors: A critical review

期刊论文

Recent advances in SERS detection of perchlorate

Jumin Hao, Xiaoguang Meng

期刊论文

基于先验形状和局部统计的血管影像图像分割方法

Yun TIAN, Zi-feng LIU, Shi-feng ZHAO

期刊论文

A fast antibiotic detection method for simplified pretreatment through spectra-based machine learning

期刊论文

Field investigation of intelligent compaction for hot mix asphalt resurfacing

Wei HU,Xiang SHU,Baoshan HUANG,Mark WOODS

期刊论文